C# 問題集

using System;

namespace BoardGame
{
class Program
{
static void Main(string[] args)
{
// Read input
string[] dimensions = Console.ReadLine().Split();
int H = int.Parse(dimensions[0]);
int W = int.Parse(dimensions[1]);

        char[][] board = new char[H][];
        for (int i = 0; i < H; i++)
        {
            board[i] = Console.ReadLine().ToCharArray();
        }

        string[] coordinates = Console.ReadLine().Split();
        int y = int.Parse(coordinates[0]);
        int x = int.Parse(coordinates[1]);

        // Modify the board
        if (board[y][x] == '.')
        {
            board[y][x] = '#';
        }
        else if (board[y][x] == '#')
        {
            board[y][x] = '.';
        }

        // Output the modified board
        for (int i = 0; i < H; i++)
        {
            Console.WriteLine(new string(board[i]));
        }
    }
}

}